Basic fibroblast growth factor increases expression of the alpha v beta 3 integrin complex on human microvascular...

Area of Science:

• Cell biology
• Molecular biology
• Angiogenesis research

Background:

• The alpha v beta 3 integrin complex on human dermal microvascular endothelial cells (HDMEC) plays a role in wound healing and angiogenesis.
• Understanding factors that modulate this complex is crucial for therapeutic development.

Purpose of the Study:

• To investigate the effects of basic fibroblast growth factor (bFGF), transforming growth factor-beta (TGF-β), and interferon-gamma (IFN-γ) on alpha v beta 3 expression in HDMEC.
• To correlate changes in alpha v beta 3 expression with alterations in cell morphology and mRNA levels.

Main Methods:

• HDMEC were stimulated with bFGF, TGF-β, and IFN-γ, individually and in combination.
• Cell surface expression of alpha v beta 3 was assessed.
• Northern blot analysis was used to determine mRNA expression levels of alpha v and beta 3 subunits.

Main Results:

• bFGF stimulation dose- and time-dependently increased cell surface alpha v beta 3 expression and induced an elongated cell morphology.
• bFGF increased beta 3 mRNA but not alpha v mRNA levels.
• TGF-β or IFN-γ alone modestly decreased alpha v beta 3 expression.
• Co-incubation with TGF-β or IFN-γ inhibited bFGF-induced increases in cell surface alpha v beta 3, beta 3 mRNA, and morphological changes.

Conclusions:

• Growth factors like bFGF and pro-inflammatory cytokines such as TGF-β and IFN-γ significantly alter alpha v beta 3 expression on microvascular endothelial cells.
• These alterations in integrin expression correlate with observable changes in endothelial cell morphology.